Denon DVD-2910 excessive vibration?

I have found with my 2910 that some CDs vibrate while others do not. I have been checking them by putting my hand on the side of the player as the CD spins up. Most DVDs are fine. I have not noticed degradation in the sound or video quality. I believe the vibration is due to some production discs being off centered or slightly off balance. I copied one of my music CDs with a vibration problem to a blank CD and the copy played flawlessly with no vibration. This same CD by the way caused my computer to vibrate as well. I believe this is also do to the high spin up speed of the player. It exagerates the vibration.

I have not had any problems with my SACDs, but if the disk is off balance, it shouldn't matter what type of disk it is.
I received a demo DVD from B&W. It made my whole cabinet shake the player was vibrating so much. I read in an online forum that other people had that problem with that demo disk. I contacted B&W and they sent me another. No vibration.
What Wahoo_Envy describes as the CD vibrating on the first few tracks and then vibrating less as the disk is playing I believe is due to the fact that the laser tracks from the inside out. As the laser moves toward the outside edge of the disk, the disk spins slower. Thus less vibration.
I also tried updating my firmware and re-initialized my player. That did not make any significant difference as far as vibration with the problematic disks.

Here is a very good article which discusses CD balance issues http://www.mscience.com/faq17.html. Redbook CDs have a particular problem with high speed drives due to the lower tolerance standards for the center hole.
The Denon 2910 spins at a high speed and has a large buffer. I do believe that is why it is less tolerant of unbalanced disks.

Please use this URL http://www.mscience.com/faq17.html
There is an extra period at the end of the one I posted.

I would venture to guess, that if your Denon unit is consistantly vibrating significantly on most or all disks, that would signify a problem with the transport unit. If it just happens on the occasional disk and is not shaking to the point that you can actually hear it, then that would probably be within tolerance. As I said, my machine just vibrates on a few disks, most are fine so that would indicate to me that I don't have a problem with the transport. Also depends on your interpretation of vibration. A slight vibration when the disk is spinning I believe is normal.
If anyone can actually identify a known problem with the 2910 and report the fix, please do.

I would not argue that Theduke's player does not have a problem. Or that others who have posted describing their issues with their players may not actually have mechanical problems. I am just describing the experience that I had with my player. I find that 3 or 4 of my CDs consistantly vibrate. I made copies of a couple of them and the copies don't vibrate at all. DVDs don't vibrate nor do my SACDs. This dosn't change if the player is cold or warm or how many CDs I have played before. So I put out the theory that it may be the disks being out of balance that is causing it. The mscience article I mentioned above seems to support that.